[python] Cache venv and uv cache using prepareCache. by gscho · Pull Request #15407 · vercel/vercel

gscho · 2026-03-06T18:38:35Z

This introduces caching of the.venv and UV_CACHE_DIR directories using the build output API prepareCache. We currently used the default UV_CACHE_DIR but now we set that to a folder within the .vercel repo for consistency.

Note

Low Risk Change

This PR adds build caching functionality for Python virtualenv and uv cache directories, with no changes to auth, database schemas, billing, or security controls.

Adds prepareCache function to cache .venv and UV_CACHE_DIR directories
Introduces getUvCacheDir helper to set cache path under .vercel/python/cache/uv
Adds comprehensive unit tests for cache preparation logic

^{Risk assessment for commit 71828d8.}

Signed-off-by: gscho <greg.c.schofield@gmail.com>

changeset-bot · 2026-03-06T18:38:46Z

🦋 Changeset detected

Latest commit: 71828d8

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
@vercel/python	Patch
vercel	Patch

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github-actions · 2026-03-06T18:40:00Z

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github-actions · 2026-03-06T18:40:15Z

🧪 Unit Test Strategy

Comparing: 0f1fa86 → 71828d8 (view diff)

Strategy: Affected packages only

✅ Only testing packages that have been modified or depend on modified packages.

Affected packages - 2 (5%)

@vercel/python
vercel

Unaffected packages - 38 (95%)

@vercel-internals/get-package-json
@vercel/backends
@vercel/build-utils
@vercel/cervel
@vercel/cli-auth
@vercel/client
@vercel/config
@vercel/detect-agent
@vercel/edge
@vercel/elysia
@vercel/error-utils
@vercel/express
@vercel/fastify
@vercel/firewall
@vercel/frameworks
@vercel/fs-detectors
@vercel/functions
@vercel/gatsby-plugin-vercel-builder
@vercel/go
@vercel/h3
@vercel/hono
@vercel/hydrogen
@vercel/koa
@vercel/nestjs
@vercel/next
@vercel/node
@vercel/oidc
@vercel/oidc-aws-credentials-provider
@vercel/python-analysis
@vercel/redwood
@vercel/related-projects
@vercel/remix-builder
@vercel/routing-utils
@vercel/ruby
@vercel/rust
@vercel/static-build
@vercel/static-config
examples

Results

Unit tests: Only affected packages will run unit tests
E2E tests: Running in parallel via E2E Tests workflow
Type checks: Only affected packages will run type checks

This comment is automatically generated based on the affected testing strategy

Signed-off-by: gscho <greg.c.schofield@gmail.com>

…m/vercel/vercel into gscho/BE-291-python-build-caching

This PR was opened by the [Changesets release](https://github.com/changesets/action) GitHub action. When you're ready to do a release, you can merge this and the packages will be published to npm automatically. If you're not ready to do a release yet, that's fine, whenever you add more changesets to main, this PR will be updated. # Releases ## @vercel/build-utils@13.7.0 ### Minor Changes - [python] add support for module-based entrypoints for cron jobs ([#15393](#15393)) - For the django frontend, dynamically load settings.py instead of parsing it ([#15367](#15367)) ### Patch Changes - Updated dependencies \[[`83e804013528fc54de31082960ae31f58339bd71`](83e8040), [`921314f958c4ec85adb09e020310a5becb7f866c`](921314f)]: - @vercel/python-analysis@0.9.0 ## vercel@50.29.0 ### Minor Changes - Add interactive mode to `webhooks create` and change warning prefix from `WARN!` to `WARNING!` ([#15406](#15406)) ### Patch Changes - Updated dependencies \[[`32e8ba5f593fdeddeb63d241d7806d6c12fffe76`](32e8ba5), [`83e804013528fc54de31082960ae31f58339bd71`](83e8040), [`0f1fa86770a35d0192d64d36cb46d932e1d2a12a`](0f1fa86), [`813f3d324404237e3806530b465625ea33816370`](813f3d3), [`0a78892b1e155eb4b587a8b84c4e6814f750697f`](0a78892), [`9a973a704b7350e19d0c3ac8e110ce55eea795b2`](9a973a7), [`c6f5ac6c11fb7f431b5fb634a7fb321b10c829af`](c6f5ac6), [`921314f958c4ec85adb09e020310a5becb7f866c`](921314f)]: - @vercel/next@4.15.42 - @vercel/build-utils@13.7.0 - @vercel/python@6.21.0 - @vercel/detect-agent@1.1.1 - @vercel/static-build@2.8.46 - @vercel/backends@0.0.42 - @vercel/elysia@0.1.45 - @vercel/express@0.1.54 - @vercel/fastify@0.1.48 - @vercel/go@3.4.3 - @vercel/h3@0.1.54 - @vercel/hono@0.2.48 - @vercel/hydrogen@1.3.5 - @vercel/koa@0.1.28 - @vercel/nestjs@0.2.49 - @vercel/node@5.6.12 - @vercel/redwood@2.4.9 - @vercel/remix-builder@5.6.0 - @vercel/ruby@2.3.2 - @vercel/rust@1.0.5 ## @vercel/fs-detectors@5.9.0 ### Minor Changes - [python] add support for module-based entrypoints for cron jobs ([#15393](#15393)) ### Patch Changes - [python] add support for Python worker services with Django tasks ([#15396](#15396)) ## @vercel/python@6.21.0 ### Minor Changes - [python] add support for module-based entrypoints for cron jobs ([#15393](#15393)) - Avoid doing entry point detection on every request to a python dev server ([#15365](#15365)) - For the django frontend, dynamically load settings.py instead of parsing it ([#15367](#15367)) ### Patch Changes - speed up python entrypoint detection ([#15402](#15402)) - Add Python builder cache preparation for Build Output API v3 cache globs, the builder virtualenv, and the repo-local uv cache. ([#15407](#15407)) - Updated dependencies \[[`83e804013528fc54de31082960ae31f58339bd71`](83e8040), [`921314f958c4ec85adb09e020310a5becb7f866c`](921314f)]: - @vercel/python-analysis@0.9.0 ## @vercel/python-analysis@0.9.0 ### Minor Changes - [python] add support for module-based entrypoints for cron jobs ([#15393](#15393)) - For the django frontend, dynamically load settings.py instead of parsing it ([#15367](#15367)) ## @vercel/backends@0.0.42 ### Patch Changes - Updated dependencies \[[`83e804013528fc54de31082960ae31f58339bd71`](83e8040), [`921314f958c4ec85adb09e020310a5becb7f866c`](921314f)]: - @vercel/build-utils@13.7.0 ## @vercel/cervel@0.0.29 ### Patch Changes - Updated dependencies \[]: - @vercel/backends@0.0.42 ## @vercel/client@17.2.54 ### Patch Changes - Updated dependencies \[[`83e804013528fc54de31082960ae31f58339bd71`](83e8040), [`921314f958c4ec85adb09e020310a5becb7f866c`](921314f)]: - @vercel/build-utils@13.7.0 ## @vercel/config@0.0.38 ### Patch Changes - Fix type generation ([#15386](#15386)) ## @vercel/detect-agent@1.1.1 ### Patch Changes - Add Antigravity agent detection via `ANTIGRAVITY_AGENT` environment variable ([#15413](#15413)) - Detect Codex when `CODEX_CI` or `CODEX_THREAD_ID` is present. ([#15412](#15412)) ## @vercel/elysia@0.1.45 ### Patch Changes - Updated dependencies \[]: - @vercel/node@5.6.12 ## @vercel/express@0.1.54 ### Patch Changes - Updated dependencies \[]: - @vercel/node@5.6.12 - @vercel/cervel@0.0.29 ## @vercel/fastify@0.1.48 ### Patch Changes - Updated dependencies \[]: - @vercel/node@5.6.12 ## @vercel/gatsby-plugin-vercel-builder@2.0.144 ### Patch Changes - Updated dependencies \[[`83e804013528fc54de31082960ae31f58339bd71`](83e8040), [`921314f958c4ec85adb09e020310a5becb7f866c`](921314f)]: - @vercel/build-utils@13.7.0 ## @vercel/h3@0.1.54 ### Patch Changes - Updated dependencies \[]: - @vercel/node@5.6.12 ## @vercel/hono@0.2.48 ### Patch Changes - Updated dependencies \[]: - @vercel/node@5.6.12 ## @vercel/koa@0.1.28 ### Patch Changes - Updated dependencies \[]: - @vercel/node@5.6.12 ## @vercel/nestjs@0.2.49 ### Patch Changes - Updated dependencies \[]: - @vercel/node@5.6.12 ## @vercel/next@4.15.42 ### Patch Changes - Revert "[next] vary fallback allowQuery for partial fallback shells" ([#15418](#15418)) ## @vercel/node@5.6.12 ### Patch Changes - Updated dependencies \[[`83e804013528fc54de31082960ae31f58339bd71`](83e8040), [`921314f958c4ec85adb09e020310a5becb7f866c`](921314f)]: - @vercel/build-utils@13.7.0 ## @vercel/static-build@2.8.46 ### Patch Changes - Updated dependencies \[]: - @vercel/gatsby-plugin-vercel-builder@2.0.144 ## @vercel/python-runtime@0.6.0 ### Minor Changes - [python] add support for Python worker services with Django tasks ([#15396](#15396)) - [python] add support for module-based entrypoints for cron jobs ([#15393](#15393))  > [!NOTE] > Low Risk Change > > This PR is an automated Changesets release that only updates version numbers in package.json files, CHANGELOG.md files, and deletes changeset markdown files — no functional code changes. > > - Version bumps across ~30 packages (patch/minor) > - Changelog and changeset file updates only > - Single constant update: VERCEL_RUNTIME_VERSION = '0.6.0' > > <sup>Risk assessment for [commit d3cf7ea](https://github.com/vercel/vercel/commit/d3cf7ea8deab73a058f4228f0346317fcf3e3dbc).</sup>  Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

Cache venv and uv cache using prepareCache.

2663512

Signed-off-by: gscho <greg.c.schofield@gmail.com>

gscho changed the title ~~Cache venv and uv cache using prepareCache.~~ [python] Cache venv and uv cache using prepareCache. Mar 6, 2026

vercel bot deployed to Preview March 6, 2026 18:39 View deployment

Exclude .pyc and __pycache__ from prepareCache files.

33785f6

Signed-off-by: gscho <greg.c.schofield@gmail.com>

vercel bot deployed to Preview March 6, 2026 20:17 View deployment

gscho marked this pull request as ready for review March 6, 2026 20:18

gscho requested review from a team as code owners March 6, 2026 20:18

ricardo-agz approved these changes Mar 6, 2026

View reviewed changes

gscho enabled auto-merge (squash) March 6, 2026 21:32

Merge branch 'main' into gscho/BE-291-python-build-caching

26caf61

vercel bot deployed to Preview March 6, 2026 22:15 View deployment

gscho added 2 commits March 6, 2026 19:16

Don't use uv cache dir for vc dev.

b922068

Signed-off-by: gscho <greg.c.schofield@gmail.com>

Merge branch 'gscho/BE-291-python-build-caching' of https://github.co…

71828d8

…m/vercel/vercel into gscho/BE-291-python-build-caching

vercel bot deployed to Preview March 7, 2026 00:17 View deployment

gscho merged commit 813f3d3 into main Mar 7, 2026
225 of 227 checks passed

gscho deleted the gscho/BE-291-python-build-caching branch March 7, 2026 00:58

vercel-release-bot mentioned this pull request Mar 6, 2026

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[python] Cache venv and uv cache using prepareCache.#15407

[python] Cache venv and uv cache using prepareCache.#15407
gscho merged 5 commits intomainfrom
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